Season's first tropical depression forms

By: Dr. Jeff Masters , 3:43 PM GMT on May 28, 2009

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Nature is jumping the gun a bit this year, with the season's first tropical depression forming four days before the official start to hurricane season. The area of disturbed weather (91L) that we've been watching, about 250 miles east-northeast of Cape Hatteras, North Carolina, has developed enough heavy thunderstorm activity and spin to be classified as a tropical depression. QuikSCAT imagery from last night revealed a closed surface circulation, but top winds of only 20 - 25 mph. Satellite estimates (using a cloud pattern recognition method called the "Dvorak" technique) were saying this was a tropical depression this morning, though, so the NHC elected to upgrade the system.

The disturbance is over the relatively warm waters of the Gulf Stream (25°C) and has wind shear of 5 - 10 knots over it, and these conditions are marginally favorable for some slow development to occur until Friday, when the system will likely move over waters too cold to support intensification. TD One is not a threat to any land areas. I give the storm a 60% chance of becoming Tropical Storm Ana.


Figure 1. Latest satellite image of TD One.

Is the formation of TD One a harbinger of an active hurricane season?
Probably not. Early season storms occurring near the U.S. coast have not been shown to be correlated with an active main portion of hurricane season during August - October. However, the situation is different if we start getting June and July storms in the deep tropics between Africa and the Lesser Antilles Islands. This was the case last year, when the formation of Hurricane Bertha in the deep tropics in July presaged an active 2008 hurricane season. According to the Hurricane FAQ, "as shown in (Goldenberg 2000), if one looks only at the June-July Atlantic tropical storms and hurricanes occurring south of 22°N and east of 77°W (the eastern portion of the Main Development Region [MDR] for Atlantic hurricanes), there is a strong association with activity for the remainder of the year. According to the data from 1944-1999, total overall Atlantic activity for years that had a tropical storm or hurricane form in this region during June and July have been at least average and often times above average. So it could be said that a June/July storm in this region is pretty much a "sufficient" condition for a year to produce at least average activity."

Portlight.org offering relief to Florida flood victims
Tropical disturbance 90L dropped as much as two feet of rain over Northeastern Florida last week, causing severe flooding. In Volusia County, at least 1500 homes were damaged by the flooding, and many of these were in low-income housing projects where the residents did not have flood insurance. Portlight Strategies, Inc., is now working to assist in this area by providing durable medical equipment to the disabled, elderly, or injured that have lost equipment due to the flooding. Equipment will also be provided to local shelters and other organizations working with flood victims. To help out, visit the Portlight disaster relief blog..


Figure 2. Rainfall amounts over Florida for the two weeks ending on May 27, 2009. Images credit: NOAA.

Jeff Masters

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Quoting TampaSpin:


Mishy...hey girl
Hi Spin how are you?
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Quoting TampaMishy:
Hi Cane


Mishy...hey girl
Member Since: September 2, 2007 Posts: 179 Comments: 20448
Hi Cane
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151. beell
140.
Thanks for the links, Skye. Don't remember ever seeing a squall line plotted on these things but was having trouble "seeing" a surface trough just west of the FL Straits. That might not mean much lol! The other two-verified by the sat loop.

Maybe some extra funding could get some extra symbols!

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150. IKE
Quoting nrtiwlnvragn:


As of 18Z

...INITIAL CONDITIONS...
LATCUR = 37.4N LONCUR = 70.2W DIRCUR = 50DEG SPDCUR = 13KT
LATM12 = 36.1N LONM12 = 72.9W DIRM12 = 45DEG SPDM12 = 14KT
LATM24 = 34.4N LONM24 = 74.6W
WNDCUR = 30KT RMAXWD = 40NM WNDM12 = 25KT
CENPRS = 1006MB OUTPRS = 1011MB OUTRAD = 100NM SDEPTH = M
RD34NE = 0NM RD34SE = 0NM RD34SW = 0NM RD34NW = 0NM



Well...I was close.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
Here's a final bit of GREAT NEWS concerning the XtremeHurricanes.com live cam / remote hurricane weather station test.

Abacast.com has just sent me the JAVA script that fixes the bug in the embedded player when using Internet Explorer.

I have inserted the corrected script into the html file and it is now up and running CORRECTLY without any bugs at all.

That was the final fix, folks.

This remote hurricane station is officially now ready for deployment! [Woot!]
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Quoting Weather456:
TD 1 reminds me of the unnamed tropical storm of July 2006.



uhhh that would be great to look up on :)
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Quoting IKE:
Looks like it's moving ENE...it being TD1.


As of 18Z

...INITIAL CONDITIONS...
LATCUR = 37.4N LONCUR = 70.2W DIRCUR = 50DEG SPDCUR = 13KT
LATM12 = 36.1N LONM12 = 72.9W DIRM12 = 45DEG SPDM12 = 14KT
LATM24 = 34.4N LONM24 = 74.6W
WNDCUR = 30KT RMAXWD = 40NM WNDM12 = 25KT
CENPRS = 1006MB OUTPRS = 1011MB OUTRAD = 100NM SDEPTH = M
RD34NE = 0NM RD34SE = 0NM RD34SW = 0NM RD34NW = 0NM

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Hello again, foul weather friends. So begins another season.
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Quoting NEwxguy:


yep,we have the distinction of being the coldes part of the conus


Next week is suppose to be in the 70's. We shall see.
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144. IKE
Looks like it's moving ENE...it being TD1.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
Quoting breald:


I think we were the coldest spot in the lower 48 states. BRRRR!!!


yep,we have the distinction of being the coldes part of the conus
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I figured the blog would be busier today with a TD out there. Guess not.

I would expect this to be TS Ana. I assume the next update will be at 5 PM since this isn't close to land.
Member Since: April 26, 2009 Posts: 3 Comments: 3667
Quoting NEwxguy:
Even with the gulf stream in the area,its got to be feeling the effects of the cold ocean,the waters here in new england are still in the low 50's


I think we were the coldest spot in the lower 48 states. BRRRR!!!
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140. Skyepony (Mod)
beell~ Your right, they are trofs, prefrontal or otherwise. The one over MX would be just that. The discussion points them out & it matches up well with the map. The 2 infront of the front just happen to be prefrontal troughs. Would help if they held to their symbols..

Learning them in Black & White has held down the confusion here.
Member Since: August 10, 2005 Posts: 190 Comments: 38618
139. TX2FL
Quoting presslord:
Do y'all remember 'Stoopid' from last year? His response to Hebert Boxes was 'The Stoopid Circle'...he drew a huge circle encompassing all of the US East and Gulf coasts, Central America, and the Carribean...it was hilarious...


I remember that, the first time I saw it I laughed so hard..and I forwarded it to all of my SoFla and former Texas co-workers. It's always nice for a little humor to be injected.

Now, what are the statistics on May TD's that don't make it to TS status?
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138. SRQfl
Quoting Weather456:
CNN reported in one of their polls that the majority of persons living in hurricane prone areas are not prepared for the upcoming season with a lack of a diaster plan and hurricane supply kit.

What do you mean? I have plenty of hurricane party supplies and plenty of surf wax...lol
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137. beell
Quoting Skyepony:
Recon is pretty late with the plan of the day..

On the "fronts" feature the yellow dotted are prefrontal troughs. The blue triangled line the cold front.


It had always been my understanding that the yellow dashed line marked a surface trough. Pre-frontal or otherwise. Now I am confused! CF-easy to ID.
Thanks.
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NDBC

MAY 28 2009.
Station 41025 - Diamond Shoals



Station 41025
NDBC
Location: 35.006N 75.402W
Conditions as of:
Thursday, May 28, 2009 12:50:00 PM

Winds: SSW (210°) at 7.8 kt gusting to 9.7 kt
Significant Wave Height: 3.3 ft
Dominant Wave Period: 7 sec
Atmospheric Pressure: 29.89 in and falling
Air Temperature: 76.5 F
Dew Point: 67.6 F
Water Temperature: 79.3 F

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Orca...my mother in law has been here since Sunday....please give me a break...
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Even with the gulf stream in the area,its got to be feeling the effects of the cold ocean,the waters here in new england are still in the low 50's
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Pat expressed my sentiments far more eloquently than I did...
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Just thought I'd point out that this is NOT the first time that a May storm has formed for 3 consecutive years: the years 1932-34 all also had storms in May.

Anyway, in regards to TD 1, it hasn't really changed much since this morning. I still think it might reach TS status, but the convection has been warming a little and SST's are decreasing, so it's looking a little less likely.
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3 hours to go.
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130. Skyepony (Mod)
Recon is pretty late with the plan of the day..

On the "fronts" feature the yellow dotted are prefrontal troughs. The blue triangled line the cold front.
Member Since: August 10, 2005 Posts: 190 Comments: 38618
TD 1 reminds me of the unnamed tropical storm of July 2006.

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Quoting presslord:
...although I'm about to the point I think we should just turn their country into a big sheet of glass....


I can't believe you of all people could actually say that?
Member Since: October 1, 2007 Posts: 81 Comments: 26511
yea Pat...maybe we can just turn Kim Jong Il into a block of salt....
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126. MahFL
anyone see a pinhole eye yet ?
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The N Koreans are a good people.

Their Leaders however,should all be made into Kim-Chee and buried real deep.

But that's a entry for another day,..
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124. MahFL
That General would "kick ass" for sure.......
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...although I'm about to the point I think we should just (blah, blah, blah...)
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Gen Honore,Ret..would make a Great Secy of Defense,or VP one day.


Sure nuff'
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@ Baltocane
Were ya there for Isabel? I was at the end of Bond Street Wharf watching waves kick thru the pier and waving a bottle of rum around screaming "ISSAAABEEELLLL".

PS. The Boh tat on my arm bore witness... oh the things his one eye have seen.
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you're right Pat...he IS da man...
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well it looks the NHC are not issuing immediate advisories (2 & 8) with this one due to its distance from land.
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Quoting 7544:
hi pat, tampa and everyone looks like we will beseeing ANA IN THE NEXT 6 HOURS staytuned can she make it >?


Ya possibly so..I give it less than 30% chance...But 30% is a chance.
Member Since: September 2, 2007 Posts: 179 Comments: 20448
Ana could be named come the 8pm EST Advisory.

Stay tuned.
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116. 7544
hi pat, tampa and everyone looks like we will beseeing ANA IN THE NEXT 6 HOURS staytuned can she make it >?
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Quoting Orcasystems:


I put them into Google.. I wonder how long until someone goes stir crazy



What if you happen to live in one of the boxes... That can't be good.
Member Since: April 26, 2009 Posts: 3 Comments: 3667
Oooh..Lemme tune in the General.
He's Da Man.
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Real-Time Tropical Cyclone Products - Description of Products

Overview

The purpose of this web site is to display in a real-time manner tropical cyclone products created and/or developed by NOAA/NESDIS/STAR/RAMMB and associated CIRA scientists over the last 20 years. While there is some overlap with other tropical cyclone web pages an effort has been made to show unique products not displayed elsewhere. To serve these data to the public the web page is also integrated to a database that can accommodate future product development. Because the site is a developing project, current products may be unavailable at earlier times.
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Pat...General Honore is about to be on CNN discussing what we should do about N Korea...and I'm pretty sure I butchered the spelling of his name....
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CNN reported in one of their polls that the majority of persons living in hurricane prone areas are not prepared for the upcoming season with a lack of a diaster plan and hurricane supply kit.
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Quoting Orcasystems:


I looked.. umm what record?


1st ever 3 consecutive may storms (tropical & subtropical), the remainder are statistics.
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Storm Relative 1km Geostationary Visible Imagery

Time of Latest Image: 200905281715




2km Storm Relative IR Imagery with BD Enhancement Curve
Time of Latest Image: 200905281715



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Quoting Chicklit:

Someone else something funny to say regarding the cat box and the Hebert boxes...cannot remember what it was!


I put them into Google.. I wonder how long until someone goes stir crazy

Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting Weather456:
Good Afternoon....

Tropical Depression 1 sets records


Thanks. Forgot all about the EPAC
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Thanks haha. I thought so. Keep up the good work you guys... back to lurkmode.
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Blog Update
Reflector site for those at work, which now also includes Weather456, daily updates


TD 1

AOI #2
Member Since: October 1, 2007 Posts: 81 Comments: 26511

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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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